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import std/strutils
import std/strformat
import std/sequtils
import std/algorithm
import std/sugar
type
Tree = tuple
height: int
found: bool
proc scanTree(tree: Tree, answer: var int, maxHeight: var int): Tree =
result = tree
if tree.height > maxHeight:
maxHeight = tree.height
if not tree.found:
answer += 1
result = (tree.height, true)
proc calculate(row: var seq[Tree], reved = false): int =
var
answer = 0
maxHeight = -1
newRow: seq[Tree]
if reved:
newRow = row.reversed()
else:
newRow = row
for i, r in newRow:
newRow[i] = scanTree(r, answer, maxHeight)
row = newRow
return answer
func part1(content: seq[string]): int =
var grid = map(
content,
(row) => zip(map(row, (c) => ord(c) - ord('0')), newSeq[bool](row.len()))
)
var answer = 0
for row in grid.mitems():
answer += calculate(row)
answer += calculate(row, true)
for i in 0 ..< grid.len():
var col = map(grid, (row) => row[i])
answer += calculate(col)
answer += calculate(col, true)
return answer
func checkVisibility(line: seq[int], height: int): int =
result = 0
for h in line:
result += 1
if h >= height:
return result
return result
proc part2(content: seq[string]): int =
let grid = map(content, (row) => map(row, (c) => ord(c) - ord('0')))
result = 0
for i, row in grid:
for j, h in row:
var col = map(grid, (row) => row[j])
var count =
checkVisibility(row[j+1 .. ^1], h) *
checkVisibility(row[0 .. j-1].reversed(), h) *
checkVisibility(col[i+1 .. ^1], h) *
checkVisibility(col[0 .. i-1].reversed(), h)
# echo fmt"{i}, {j} = {count}"
result = max(result, count)
return result
let content = readFile("./input.txt").strip().splitLines()
echo part1(content)
echo part2(content)
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